Apparatus for metering conversations in automatic telephone-exchanges.



G. GRABB.

APPARATUS FOR MBTERING CONVBRSATIONS IN AUTOMATIC TELEPHONE EXCHANGES.

APPLICATION FILED JULY 28,1910.

1,020,9'76, Patented Mar. 26, 1912.

UNITED STATES PATENT OFFICE;

GEORG GRABE, 0F NIKOLASSEE, NEAR BERLIN, GERMANY, ASSVIGNOR. T0 SIEMENS &

HALSKE A. G., 0F BERLIN, GERMANY, A CORPORATION 0F GERMANY. 4

APPARATUS FOR METERING CONVERSATIONS IN AUTOMATIC TELEPHONE-EXCHAN GES.

. .Specification of Letters Patent.

Patented Mar. 26, 1912.

Application filed July 28, 1910. Serial No. 574,257.

To all whom it may concern Be it known that I, GEORG GRABE, a subject of the German Emperor, and 'residing at Nikolassee, near Berlin, Germany, have invented certain new and useful Improvements in Apparatus for Metering Conversations in Automatic Telephone-Exchanges, of which the following is a specification.

This invention relates to apparatus for metering conversations in automatic telephone exchanges, in which the metering takes place after the termination of the conversation. In contradistinction to former arrangements, in which the selectors and connectors utilized for a connection are released simultaneously with the metering of the conversation, according to my invention the release of the connectors and selectors is retarded or takes place only after metering has been effected. To this end, at the termination of the conversation after the line relay located at the connector has become currentless or has operated, a connection is brought about which causes the first selector first to meter at the calling subscribers line by means of an additional change over, and then by means of a subsequent reversal to bring about the releases of the selectors and the connector occupied for the connection.

According t'o my invention the testing and releasing lines are closed backward upl to the firstselector in succession by way of t e coils of the auxiliary relay as soon as the line relay of one of the speaking subscribers located at the connector has become currentless and without a releasing relay being actuated or a relay which serves at the iirst selector for influencing the meter of the calling stationby way of another branch of the connecting line closed in the meantime at the connector, whereupon the connector is released by interrupting the testing line to the second' selector at the first selector and by interrupting the'testing lines in -turn by means of the auxiliary relays. This is brought about, according to my invention,

by the side or controlling switch of the connector beingplaced one step beyond the through position after the line relay of the calling or called subscriber located at .the connector has become currentless. In this position the testing line leading from the connector to the last selector is closed by way of the winding of an auxiliary relay which interpolates the electromagnet of the side or controlling switch in a holding circuit, the testing relay of the last selector closes the testing line to the precedin selector in the row by way of the coil o a like auxiliary relay, and so on until the testing relay of the first selector connects in circuit the controlling switch electromagnet by way of an interrupter. Then the controlling switch at the first selector will be brought one step forward and arrives into a position, in which a relay at the first selector for starting the movement of the meter of the subscribers lines is energized by way of a branch line closed at the connector. Owing to the controlling switch at the first selector being automatically fed forward a second time, the-testing line to the second selector is now interrupted and the stepwise interruption of the testi-ng lines and the further movement of the controlling switch of the connectors for interpolating the circuits of the releasing magnets are brought about by means of the auxiliary relays.

In order aftermetering has taken place, and the releasing circuits at the controlling switches have been interpolated, to prevent the connector being advanced when the telephone is hung up at the calling station only, and to prevent the first selector in the row being advanced when the telephone is hung up only at the called station, according to my invention the calling subscribers line relay which is located at the'connector and when currentless brings about the interpolation of the releasing circuit is connected by the controlling switch into a holding circuit, while the line relay at the first selector is connected to the calling line.

One illustrative embodiment of my invention is represented diagrammatically by way y of example in the accompanying drawing;

Referring to the drawing, 133 designates a callingfstation which is connected with a called station 2655 by way ot the re-selector VWS-a, two selectorsk GW an GW and the connector L'W. In the drawing the selectors and connector are Shown in the position during the conversation. only those parts of the connection and apparatus being shown, for the sake of clearness, which are requisite for understanding the connection of the releasing and metering circuits at the known pre-selectorsl and- Strowger selectors.

The coil lof the testing and disconnecting relay TR22 at the ypre-selector VWf3 is interpolated for the duration of the connection in a holding .circuit by way of the testing line c1 of the selector GW1 `and holds the branches am, 71122 connected with the branches a1, b1 by way of the cont-acts t1, t2 and the contact arms 01, 02 of the selector GW1. The meter ZR22 is connected in shunt with the coil l oite the relay TR32 and the current flowing from the -lpole of the exchange battery by way of the contact n1 of the releasing magnet N, series resistances w1, lw2, testing l1ne 01, contact arm 03, coil l of relay TR38 and coil of meter 2R23, contact'ts, contact 1 of the pulling switch does not suiiice, on the one hand, for energizing the meter magnet and produces, on the other hand, a fall of voltageat the testing line c1 which makes this appear occupied, as another subscribers relay TR testing with its high resistance coil 2 on this line cannotl obtain sufficient current to excite it. At the selector GW1 the levers s of the controlling switch are in the fifth, z'. e. the through position, in which the branches a1, b1 are connected with the branches a2, b2 of the selector GW2 by way of the levers s1, s2 of the controlling switch and the selector arms o2, 05, while the line relays A, B, X are disconnected from the branch line. The low resistance coil l of the testing relay P of the selector GW1 is here connected by way of the switch levers s3, s4 and the selector arrn o6 to the test line c2, which is connected with the coil of an auxiliary relay Q1 at the selector GW2 by way of a series resistance lw2 and the switch lever 312 of the controlling switch of the second selector GW2. The relays P and Q1 are currentless, however, as the circuit is broken in the through position at the armature of the testing re ay P1. A

At the selector GW'2 the controlling switch levers are in the fourth position, which is 'likewise the through position, vand the branch lines a2, b2 are connected with the branch lines a2, b2 leading to the connector LW by way of the switches s2, s2 of the controlling line relays A1, B1, X1 of this selector are disconnected. The low resistance coil l of the testing relay P1 is connected by way of the switches 811, 81 and the selector arm 02 with the test line c2 which, however, is interrupted at the switch S12 of the controlling switch of connector LW. At the connector LW the controllingA switch is in t-he sixth or through position, and the branch lines a2, b2 are conected by way of the switches s1, s1, the condensers k1, k2 and the selector arms` 01, 011 with the branch lines a5, Z155 which lead to the subscribers station 2655.

The line relays A2, B2, X2 are connected in front of the condensers k1, 7a2 located in switch and the selector arms o, o2, while 'the the branches of the telephone line in bridge connection with the branch lines a2, b2, and the choking coil Dr and the supervisory relay Y are connected behind the condensers in bridge connection with the branch lines c55, Z955. The coils l, 2 of the relay TR55 of the called subscriber 2655 are energized for the duration of the connection by way of the switch s, connector arm 012, line c55 and series resistance @05 and hold the line relay of the subscriber disconnected from the branch lines a, 555,' simultaneously, line c55 is subjected to a testing voltage 'which prevents the connection of a second connector to the line of the subscriber 2655.

The microphone current for the subscriber flows from the -lpole of the battery by Way of relay B2, coil l of the ditl'erential-relay X2, branchv line b3, selector arm 02, switch lever s2, branch line b2, selector arm 05, switch lever s2, branch line b1, preselector arm 02, contact t2, branch line 11132', station 133, branch line (1122, contact t1, pre-selector arm o1, branch line 0:1, switch lever s1, selector arm o, branch line a2, switch lever 82, selector arm o", branch line a3, coil 2 of the relay X2, relay A2 and back to the battery, The feeding current for the subscriber 2655 flows from the -lpole of thebattery by way of relay Y, switch lever 816, connector arm y 011,' branch line 555, station 2655, branch line c55, connector arm 01, switch lever S12,

choking coil Dr and back to the battery.

Consequently, the relays A2, B2, Y are energized during the conversation, but not the diierential relay` X2 because the two' coils 1, 2 oppose one another.

As soon las the calling or the called subscriber hangs up his telephone, owing to the relay B2 or Y, respectively, becoming currentless the electromagnet S2 of the'controlling switch is connected by way, of switch lever 82 in position 6, contact b2 of the relay B2 or contact g/ of the relay Y, in a circuit leading from the batt-ery by way of the interrupter U.v In this manner the controlling switch is brought from the sixth into the seventh position. In this position the branch line a3 is disconnected 'at the switch 815 from the branch line c55 and connected by Way of the coil of the relay B2 with the -l-l pole of the battery, so that a current now flows from the' +.pole ot the battery by way of relay B2, switch lever s1", coil 2 of the differential relayX2 and relay A2 to the pole ofthe battery, while the test line c2 is connected at the switch 812 with the coil of the relay Q2. Another current arises, which flows from the pole of t-he battery by way of switch lever .511, coil 1 of the relay P1, switch lever s1", selector arm o, test line c2, resistance w1, switch lever 512. relay Q2 to the pole of thebattery which energizes the relays Q2 and P1, there being at the test line c2 a fall of voltage which prevents the excitation of a relay P1 of another second selector testing in known manner with the high resistance coil 2. The relay Q2 interpolates the electromagnet S2 at the contact 2 in a .holding circuit, while by closing t e contact p1 the relay P1 causes a current to flow from the pole of the battery by vway of the switch lever s2, coil l of relay P, switch lever s4, selector arm o, test line c2, resistance wa, switch lever 812, relay Q1, contact p1 to the pole of the battery. The relay Q1 interpolates at its contact g1 the electromagnet S1 of the controlling switch at the selector GrW2 in a holding circuit, while the relay P connects the electromagnet S of the first selector at the contact p to the battery by way of the interrupter U. After the circuit has been closed and subsequently opened at the interrupter U the controlling switch at t first selector is moved 4on from the lift-h int the sixth position. In this position the relay Z connected with the pole is connected by way of the switch s to the branch line a2, while the branch lines a1, b1 are connected again with the line relays A,`B, X

Aby wa of the switches s1 and s. A current flows rom the pole of the battery by way of the coil of the relay B2 at the connector LW, switch lever 815 in position 7, branch line a2, selector arm o1, switch lever sa, branch line a2, selector arm 04,y switch lever ole of the battery. The current flowing to t e pole of the battery from the branch line a3 by way of the coils of the relays X2, A2 is onl small on account ofthe high resist-ance o" these relay coils in comparison with that of the coil of the relay Z. By attracting .its armature the relay Z short circuits the series resistance w1, so that a heavy current flows from the pole 4of the. battery by way of the contact z, resistance w2, test line c1, pre-selector arm o, the coils of the meter ZRas and relay TR83 connected in parallel, contacts t3, 1 to. the ole of the battery, so that the meter of su scriber 133 is fed forward. Further, in the sixth position of the controlling switch the electromagnet S is connected directly with the interrupter U and when the circuit at the interrupter is next closed and/ opened the controlling switch is brought by the electromagnet S from the sixth into the 4seventh position. In this i position the releasing electromagne'ts M and N of the'rst selector GW1 and the controlling switch of the latter are connected at the switch s" with the rest contact of the relay B and they are interpolated as soon its no `current flows over the subscribers Further, in the seventh position of the controlling switch the test line c2 is interrupted at the switch s* and the relay Q1 which has consequently become currentless interrupts the current in the electromagnet S1, whereby the controlling switch of the second selector GW2 is moved from the fourth into the fifth position, in which the releasing, electromagnets M1 and N1 are interpolated at the switch s1* and the line o3 is interrupted at the switch s1".

The relay Q2 which has become currentless owing to the interruption of the line 12 interrupts the current in the electromagnet S2, whereupon the controlling switch of the connector passes from the seventh into the eighth position, in which the releasing electromagnets M2, N2 of the connector LW andthe controlling switch of the latter are interpolated at the switch 521. As the relay B2 is interpolated in a holding circuit leading from the 'pole of thebattery by way oi the relay B2, switch lever 312, coil 2 of the differential relay X2 and relay A2 to the pole of thebattery and holds the contact b1 open; when the cohtrolling switch is in the seventh and eighth positions, the circuit of the releasing electromagnets M2, N2 can only be closed at the connector LNV when the called subscriber 2655has hung up his receiver and the relay Y, which has thereby become currentless, has closed the contact y.

When their armatures are attracted the releasing electromagnets N, N1, N2 are connected together with the electromagnets M, M1, M2 into holding circuits which are only disconnected when the selectors open the pressing contacts Z, l1, Z2, after reaching their rest position. Thereleasing magnet N of the first selector GW1 also brings about the interruption of the line 01 at the` contact n1, whereby the relay TR33 also becomes currentless and, owing to its armature falling, connects the rotatory electromagnet D33 of the pre-selector VW23 to the battery by way of the interrupter U1, Contact r2 of the line relay R23, contact t4, contact i1, whereby the pre-selector is rotated step by ste until itl arrives into its rest position, in which the contact 1 is opened and electromaguet D83 is cut out of circuit.

I claim 1. In an automatic telephone system, the combination, with subscribers stations` a telephone and switchin means in each subscribers station, an excxange, lines for connecting the subscribers stations with the exchange, selectors and connectors for connecting a calling with a called station and testing branches for connecting the selectors with each other, releasing relays at the selectors and connectors, a meter for each subscribers station, and means for connecting and for starting the meter through the testing branch, of relays at the connector controlling the calling and called lines, switching. devices at a selector for making a circuit for the meter of the calling subscriber at the end of a conversation, switch armatures at said relays at thelconnector which are moved when the telephone is replaced at a subscribers station, means for imparting the switching movements of said armatures to the switching devices at the selectors, and means at the switching devices or closing the circuits for the releasing relays of the selectors and connectors after the meter circuits have been made.

2. In an automatic telephone system, the combination, with subscribers stations, a telephone and switching means in each subscribers station, an exchange, lines for connecting the subscribers stations with the exchange, a calling device in the exchange for each subscriber, selectors and connectors for v connecting a calling with a called station and testing branches for connecting the selectors with each other, a controlling switch at each selector and connector for bringing y about the stepwise change over of the selector circuits requisite for operating the selectors, releasing relays at the selectors and connectors a meter for each subscriber, and means for connecting and for starting the meter through the testing branch, of relays at the connector controlling the calling and called lines, switching devices at a selector for making a circuit for the meter of the calling subscriber at the end of a conversation, switch armatures at said relays at the connector which are moved when the telephone is replaced at a subscribers station, means for impart-ing the switching movements of said armatures to the switching devices at the selectors, and means at the switching devices for closing the circuits for the releasing relays of the selectors and connectors after the meter circuits have been made.

3. n an automat-ic telephone system, the combination, with subscribers stations, a telephone and .switching means in each subscribers station, an exchange, lines for conneet-ing the subscribers stations with the exchange, a calling device in the exchange for each subscriber, selectors and connectors for connecting a calling with a called station and testing branchestor connecting the selectors with each other, a controlling switch at each selector land connector for bringing about the stepwise change over of the selector circuits requisite 'for operating the selectors, releas ing relays at the selectors and connectors, a meter for each subscriber, and means for connecting and for starting the meter through the testing branch, of relays at the connector controlling the calling and called lines, switching devices at a selector for making a circuit `for the meter of the calling subscrlber 'at the end of a conversation, switch armatures at said relays at the connector which are moved when the telephone is replaced at a subscribersstation, means comprising switch arms at the controlling switches of the selectors for imparting the switching movements of said armatures to the switching devices at the selectors, and means at the switching devices for closing the circuits for the releasing relaysv ot the selectors and connectors after the meter'circuits have been made.

4. In an automatic telephone system, the combination, with subscribers stations, a telephone and switching means in each subscribers station, an exchange, lines for connecting the subscribers stations with the exchange, a calling device in the exchange for each subscriber, selectors and connectors for connecting a calling with a called station and testing branches for connecting the selectors with each other, a controlling switch at each selector and connector for bringing about the stepwise change over of the selector circuits requisite for operating the selectors, releasing relays at the selectors and connectors, a meter for each subscriber, and means for connecting and for starting the meter through the testing branch, of relays at the connector controlling the calling and "called lines, switching devices at the first selector in the row for making a circuit for the meter of the calling subscriber at the end of a conversation, switch armatures at said relays at the connector which are moved when the telephone is replaced at a subscribers station, means comprising switch arms at the controlling switches of the selectors for imparting the switching movements of said armatures to the switching devices at the selectors, means at each connector and at each first selector in the row for moving the controlling switches another step in succession after the termination of a conversation, means at the' remaining selectors for locking their controlling switches until metering has taken place, means at the selectors and at each connector for releasing the latter locked controllingl switches after the meter circuits have been made, and means at the switching devices for closing the circuits for the releasing relays of the selectors and connectors after the meter circuits have been made.

5. In an automatic telephone system, thev a cont-rolling switch at each selector and.

connector for bringing about the stepwise change over of the selector circuits requisite for operating the selectors, releasing relays at the selectors and connectors, a meter for each subscriber, and means forconnecting and for starting the meter through the testing branch, of relays at the connector controlling the calling and called lines, switching devices at the first selector in the row for making a circuit for the meter of the calling subscriber at the end of a conversation, swit'ch armatures at said relays at the connector which are moved when the telephone is replaced at a subscribers station, means comprising switch arms at the controlling switches of the selectors for imparting the switching movements of said armatures to the switching devices at the selectors, an auxiliary relay lat eachconnector and at each selector, with the exception of the first selector in a'row, in series with the'testing line and the testing relay of the previous selector, switching means controlling the testing lines, testing relays and auxiliary relayls for moving the controlling switches anot er step in successiony after -the termina-- tion of a conversation, means at the remain.- ing selectors for locking their controlling switches until metering hasv taken place, means at the selectors and at eachconnector for releasing the latter locked controlling switchesafter the meter circuits-have been made, and means at the switching devices forclosin the circuits for the releasing relays of .t e selectors and connectors after the meter circuits have been made.

6. In' an automatic telephone system, the combination, with subscribers stations, a tele hone and switchin means in each subscriEers station, an exc ange, lines for connecting the subscribers stations with the ex change, a calling device in the exchange for each subscriber, selectors and connectors for connecting a calling with a called station, testing lines and'testing relays for connecting the selectors with one another, withthe connectors and with the subscribers stations, a controlling switch at each selector and connector for bringing about the stepwise change over of the selector circuits requisite for operating the selectors, releasing relays at t xe selectors and connectors a meter for each subscriber, and means' or connectin through t e :testing branch, of relays at the connector controllln the callin and called lines, switching devlces at the rst selector in the row for making a circuit for the meter of the calling subscriber at the end of a conversation, switch armatures at-said relays at the connector which are moved when the telephone is replaced ata subscribers station, means comprisin switch arms at the controlling switches o the selectors for im arting the switchin movements of said aratures to the switc ing devices at the selectors, an auxiliary relay at each connector and at each selector, with the exception of the firstv selector in a row,in series and for, starting the meterwith the testing line and the testing relay of the revious selector, switching means controlling the testing lines, testing relays and auxiliary relays for moving the controlling switches another step in succession after the termination of a conversation, the auxiliary relays being used for locking the connectors and the selectors with the exception of the first selector in a row until meter" 0 has taken place, means at` the selectors siii at each connector for releasing the latter locked controlling switches after the meter circuits have been made, and means at the switching devices for closing the circuits for the releasing relays of the selectors and connectors after the meter circuits have been` vmade.

7. In an automatic telephone system, the combination, witih` subscribers stations, a teleghone and switching means in each subscri ers station, an exchange, lines for connecting the subscribers stations with the exchange, a calling device in the exchange for each subscriber, selectors and connectors for connecting a calling with a called station, testingllnes and testing relays for connecting the selectors with one another, with the connectors and with the subscribers stations, a controllin switch at each selector and connector for ringin about the stepwise change over of the se ector circuits requisite for operating the selectors, releasing relays at the selectors and connectors, a meter for each subscriber, and means for connecting and -for starting the meter through the testing branch, of relays at the connector controlling the calling and called lines, switching devices at the first selector in the row for making a circuit for the meter of thecalling subscriber at the end of a conversation, switch armatures at said rela s at the connector which are moved when t e telephone is replaced at a subscribers station, means com risin switch arms at the controlling switclies of?9 the selectors for imparting the switching movements of said armatures to the switching devices at the selectors, an auxiliary relay at each connector and at each selector, with the exception of the first selector in a row, in series with the testing line and the 'testing relayof the revious selector, switching means controlling the testing lines, testing relays and auxiliary relays for moving the controlling switches another step vin succession after the termination of a conversation, means for conhectin the auxiliary relay of va connector in a ho ding circuit after the change, a calling'device in the exchange for each subscriber, selectors and connectors for connecting a calling with a called station, testing lines and testing relays for connect-- ing the selectors with one another, with the connectors 'and with theV subscribers stations, a controllingswtch `at each selector and connector vfor bringing about the stepwise change over ofthe' selector circuits requisite for operating the selectors, releasing relays at .the selectors and connectors, a meter for each subscriber, and means for connectingand for starting the meter through the vtesting branch; of relays at the connector r controlling the lcalling and called lines,

. switching devices at the rst selector in 'the row for making a circuit for the meter of' the calling .subscriber at the end of a conversation, switch armatures at said rela s at the connector which are moved when t e .telephone is replaced at a subscribers station, means comprising switch arms at the controlling switches,y of the selectors for imparting the switching movements of said armatures to .the switching devices at the selectors, an auxiliary relay at each connector and at each selector`,`jwiththe exception of the fjst selector in a row, in series with the testing line and the testing relay of the revious selector,. switching means controlling the testing lines, testing relays and auxiliary relays for moving the controlling switches another step in succession after the termination of a conversation, means at the remainn selectors `for locking their cont-rolling switc es until metering has taken place, means at the selectors and at noname ing relays of the selectors and connectors after the meter circuits have been made..

9. In an automatic telephone system, the combination, with subscribers stat-ions, a telephone and switching means in each subscribers station, an exchange, lines for connecting the subscribers stations with the exchange, a calling device in the exchange for each subscriber, selectors and connectors for connecting a calling with a called station, a controlling switch at each selector and connector for bringing about the stepwise change over of the selector circuits requisite l -for operating the selectors, releasing relays at the selectors and connectors, a meter for each subscriber, and means for connecting and for starting the meter through the test-- ing branch, of relays at each connector having one- 'pole connected tothe same branch of the subscribers line, condensers' interpolated in ,the subscribers lines between the relays for dividing the latter into two groups, switching devices at a selector for makino'a circuit for the meter of the calling subscriber at the end of a conversation, switch armatures at said relays atthe connector which are moved when the telephone is replaced ata subscriber-s station, means 'for imparting the switching movements of said armatures totheswitching devices. at the selectors, and means at the switching devices for closing the circuits for the releasing relays o the selectors and connectors after the meter circuits have been'made.

ln ltestil'nony whereof l have signed my name to this specification in the presence of' WoLnnMAn HAUPT,

HENRY H'Asrnn. 

